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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Hyperfine mixing in b -> c semileptonic decay of doubly heavy baryons Type Journal Article
Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 683 Issue 1 Pages 21-25
Keywords
Abstract We qualitatively corroborate the results of [W. Roberts, M. Pervin, Int. J. Mod. Phys. A 24 (2009) 2401] according to which hyperfine mixing greatly affects the decay widths of b -> c semileptonic decays involving doubly heavy bc baryons. However, our predictions for the decay widths of the unmixed states differ from those reported in the work of Roberts and Pervin by a factor of 2, and this discrepancy translates to the mixed case. We further show that the predictions of heavy quark spin symmetry, might be used in the future to experimentally extract information on the admixtures in the actual physical bc baryons, in a model independent manner.
Address [Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes ISI:000274129600005 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 501
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Author Pavao, R.; Gubler, P.; Fernandez-Soler, P.; Nieves, J.; Oka, M.; Takahashi, T.T.
Title The negative-parity spin-1/2 A baryon spectrum from lattice QCD and effective theory Type Journal Article
Year 2021 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 820 Issue Pages 136473 - 8pp
Keywords
Abstract The spectrum of the negative-parity spin-1/2 Lambda baryons is studied using lattice QCD and hadronic effective theory in a unitarized coupled-channel framework. A direct comparison between the two approaches is possible by considering the hadronic effective theory in a finite volume and with hadron masses and mesonic decay constants that correspond to the situation studied on the lattice. Comparing the energy level spectrum and SU(3) flavor decompositions of the individual states, it is found that the lowest two states extracted from lattice QCD can be associated with one of the two Lambda(1405)-poles and the Lambda(1670) resonance. The quark mass dependences of these two lattice QCD levels are in good agreement with their effective theory counterparts. However, as current lattice QCD studies still rely on three-quark operators to generate the physical states, clear signals corresponding to the meson-baryon scattering states, that appear in the finite volume effective theory calculation, are not yet seen.
Address [Pavao, Rafael; Fernandez-Soler, Pedro; Nieves, Juan] Univ Valencia, CSIC, Inst Invest Paterna, Inst Fis Corpuscular IFIC,Ctr Mixto, Apartado 22085, E-46071 Valencia, Spain, Email: gubler@post.j-parc.jp
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000713101800041 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5022
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Author Albertus, C.; Hernandez, E.; Nieves, J.
Title Exclusive c -> s, d semileptonic decays of ground-state spin-1/2 doubly charmed baryons Type Journal Article
Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 704 Issue 5 Pages 499-509
Keywords
Abstract We evaluate exclusive semileptonic decays of ground-state spin-1/2 doubly heavy charmed baryons driven by a c -> s, d transition at the quark level. Our results for the form factors are consistent with heavy quark spin symmetry constraints which are valid in the limit of an infinitely massive charm quark and near zero recoil. Only a few exclusive semileptonic decay channels have been theoretically analyzed before. For those cases we find that our results are in a reasonable agreement with previous calculations.
Address [Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000296549200017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 828
Permanent link to this record
 
 
Author Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J.
Title The nucleon axial mass and the MiniBooNE quasielastic neutrino-nucleus scattering problem Type Journal Article
Year 2012 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 707 Issue 1 Pages 72-75
Keywords
Abstract The charged-current double differential neutrino cross section, measured by the MiniBooNE Collaboration, has been analyzed using a microscopical model that accounts for, among other nuclear effects, long range nuclear (RPA) correlations and multinucleon scattering. We find that MiniBooNE data are fully compatible with the world average of the nucleon axial mass in contrast with several previous analyses which have suggested an anomalously large value. We also discuss the reliability of the algorithm used to estimate the neutrino energy.
Address [Nieves, J.] Univ Valencia, Ctr Mixto, CSIC, Inst Invest Paterna,Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: jmnieves@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000299757000010 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 903
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Author Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J.
Title Two particle-hole excitations in charged current quasielastic antineutrino-nucleus scattering Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 721 Issue 1-3 Pages 90-93
Keywords
Abstract We evaluate the quasielastic and multinucleon contributions to the antineutrino-nucleus scattering cross section and compare our results with the recent MiniBooNE data. We use a local Fermi gas model that includes RPA correlations and gets the multinucleon part from a systematic many body expansion of the W boson selfenergy in the nuclear medium. The same model had been quite successful for the neutrino cross section and contains no new parameters. We have also analyzed the relevance of 2p2h events for the antineutrino energy reconstruction.
Address Univ Valencia, Inst Invest Paterna, Inst Fis Corpuscular IFIC, Ctr Mixto,CSIC, E-46071 Valencia, Spain, Email: jmnieves@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000317326100013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1425
Permanent link to this record
 
 
Author Hidalgo-Duque, C.; Nieves, J.; Ozpineci, A.; Zamiralov, V.
Title X(3872) and its partners in the heavy quark limit of QCD Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 727 Issue 4-5 Pages 432-437
Keywords
Abstract In this Letter, we propose interpolating currents for the X(3872) resonance, and show that, in the heavy quark limit of QCD, the X(3872) state should have degenerate partners, independent of its internal structure. Magnitudes of possible I = 0 and I = 1 components of the X(3872) are also discussed.
Address [Hidalgo-Duque, C.; Nieves, J.; Ozpineci, A.] Ctr Mixto CSIC UV, Inst Invest Paterna, Inst Fis Corpuscular, Valencia 46071, Spain, Email: carloshd@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000328722500011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1665
Permanent link to this record
 
 
Author Albertus, C.; Hernandez, E.; Hidalgo-Duque, C.; Nieves, J.
Title (B)over-bar(s) -> K semileptonic decay from an Omnes improved constituent quark model Type Journal Article
Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 738 Issue Pages 144-149
Keywords
Abstract We study the f(+) form factor for the semileptonic (B) over bar (s) -> K+ l(-) (V) over bar (l) decay in a constituent quark model. The valence quark estimate is supplemented with the contribution from the (B) over bar* pole that dominates the high q(2) region. We use a multiply-subtracted Omnes dispersion relation to extend the quark model predictions from its region of applicability near q(max)(2) = (M-Bs – M-K)(2) similar to 23.75 GeV2 to all q(2) values accessible in the physical decay. To better constrain the dependence of f(+) on q(2), we fit the subtraction constants to a combined input from previous light cone sum rule by Duplancic and Melic (2008) [11] and the present quark model results. From this analysis, we obtain Gamma ( (B) over bar (s) -> K+ l(-) (V) over bar (l)) = (5.47(-0.46)(+0.54)) vertical bar Vub vertical bar(2) x 10(-9) MeV, which is about 10% and 20% higher than the predictions based on Lattice QCD and QCD light cone sum rules respectively. The former predictions, for both the form factor f(+) (q(2)) and the differential decay width, lie within the 1 sigma band of our estimated uncertainties for all q(2) values accessible in the physical decay, except for a quite small region very close to q(max)(2). Differences with the light cone sum results for the form factor f(+) are larger than 20% in the region above q(2) = 15 GeV2.
Address [Albertus, C.] Univ Granada, Dept Fis Atom Nucl & Mol, E-18071 Granada, Spain
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000344624900022 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2020
Permanent link to this record
 
 
Author Wang, E.; Alvarez-Ruso, L.; Nieves, J.
Title Single photon events from neutral current interactions at MiniBooNE Type Journal Article
Year 2015 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 740 Issue Pages 16-22
Keywords
Abstract The MiniBooNE experiment has reported results from the analysis of v(e) and (v) over bar (e) appearance searches, which show an excess of signal-like events at low reconstructed neutrino energies, with respect to the expected background. A significant component of this background comes from photon emission induced by (anti) neutrino neutral current interactions with nucleons and nuclei. With an improved microscopic model for these reactions, we predict the number and distributions of photon events at the MiniBooNE detector. Our results are compared to the MiniBooNE in situ estimate and to other theoretical approaches. We find that, according to our model, neutral current photon emission from single-nucleon currents is insufficient to explain the events excess observed by MiniBooNE in both neutrino and antineutrino modes.
Address [Wang, En; Alvarez-Ruso, Luis; Nieves, Juan] Univ Valencia, Ctr Mixto CSIC, Inst Fis Corpuscular IFIC, Inst Invest Paterna, E-46071 Valencia, Spain, Email: luis.alvarez@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000347046200003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2094
Permanent link to this record
 
 
Author Yamagata-Sekihara, J.; Garcia-Recio, C.; Nieves, J.; Salcedo, L.L.; Tolos, L.
Title Formation spectra of charmed meson-nucleus systems using an antiproton beam Type Journal Article
Year 2016 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 754 Issue Pages 26-32
Keywords Charmed mesic nuclei; Formation spectra; DN and (D)over-barN interaction; Klein-Gordon equation; Green's function method
Abstract We investigate the structure and formation of charmed meson--nucleus systems, with the aim of understanding the charmed meson-nucleon interactions and the properties of the charmed mesons in the nuclear medium. The (D) over bar mesic nuclei are of special interest, since they have tiny decay widths due to the absence of strong decays for the (D) over barN pair. Employing an effective model for the (D) over barN and DN interactions and solving the Klein-Gordon equation for (D) over bar and D in finite nuclei, we find that the D0-11B system has 1s and 2p mesic nuclear states and that the D0-11B system binds in a 1s state. In view of the forthcoming experiments by the PANDA and CBM Collaborations at the future FAIR facility and the J-PARC upgrade, we calculate the formation spectra of the [(D) over bar B--11] and [D-0-B-11] mesic nuclei for an antiproton beam on a C-12 target. Our results suggest that it is possible to observe the 2p D- mesic nuclear state with an appropriate experimental setup.
Address [Yamagata-Sekihara, J.] Oshima Coll, Natl Inst Technol, Yamaguchi 7422193, Japan, Email: yamagata@oshima-k.ac.jp
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000369601000006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2570
Permanent link to this record
 
 
Author Albaladejo, M.; Nieves, J.; Oset, E.; Sun, Z.F.; Liu, X.
Title Can X(5568) be described as a B-s pi, B(K)over-bar resonant state? Type Journal Article
Year 2016 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 757 Issue Pages 515-519
Keywords
Abstract The DO Collaboration has recently seen a resonant-like peak in the B-s pi invariant mass spectrum, claimed to be a new state called X(5568). Using a B-s pi-B (K) over bar coupled channel analysis, implementing unitarity, and with the interaction derived from Heavy Meson Chiral Perturbation Theory, we are able to reproduce the reported spectrum, with a pole that can be associated to the claimed X(5568) state, and with mass and width in agreement with the ones reported in the experimental analysis. However, if the T-matrix regularization is performed by means of a momentum cutoff, the value for the latter needed to reproduce the spectrum is Lambda = 2.80 +/- 0.04 GeV, which is much larger than a “natural” value Lambda similar or equal to 1 GeV. In view of this, it is difficult to interpret the nature of this new state. This state would not qualify as a resonance dynamically generated by the unitarity loops. Assuming the observed peak to correspond to a physical state, we make predictions for partners in the D, D*, and B* sectors. Their observation (or lack thereof) would shed light into this issue.
Address [Albaladejo, Miguel; Nieves, Juan; Oset, Eulogio; Sun, Zhi-Feng] Univ Valencia, CSIC, Inst Invest Paterna, Inst Fis Corpuscular IFIC,Ctr Mixto, Aptd 22085, E-46071 Valencia, Spain, Email: Miguel.Albaladejo@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000376800300072 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2698
Permanent link to this record